MED-JELLYRISK jellyfish dispersion model launched

Within the ambit of the MED-JELLYRISK (www.jellyrisk.eu) project, staff at the Physical Oceanography Research Group within the Department of Geosciences at the University of Malta (Dr. Anthony Galea, Mr. Denis Cutajar, Prof. Aldo Drago and Prof. Alan Deidun), with the assistance of technical staff from ISMAR-CNR in Italy, have launched a jellyfish dispersion model through which users, after registering, can track the forecasted pathway, for the next four (4) days, of a jellyfish bloom they observe in the waters around the Maltese Islands. The model is publicly available through this link.

Upon registering, users will receive an email with credentials through which to make a query to the model, by selecting the marine area where the jellyfish bloom was observed and also the extent of the bloom, density of jellyfish it held and to which species did the bloom belong. Simulations can be run for two different jellyfish species – the mauve stinger Pelagia noctiluca and the fried-egg jellyfish Cotylorhiza tuberculata – which are treated diffently by the model on the basis of differences in their hydrodynamic properties. After a few minutes, the model will output several maps showing the forecasted trajectory of the same jellyfish bloom and highlighted which coastal stretches are more likely to be impacted by beaching of the same bloom components.

The aim of the model is to implementing a decision-support system for coastal managers by providing an early warning system of the occurrence of high jellyfish densities within particular stretches. The core of the system is constituted by two different nested numerical models, an open ocean (ROSARIO6420) and a coastal area (SHYFEM) 3D hydrodynamic model. The system (ROSARIO-SHYFEM) is operational and provides daily a 4 days forecast of the main 3D hydrodynamics fields for the areas covering the Malta-Sicily Channel with a spatial resolution varying between a few km up to 50 m. The ROSARIO-SHYFEM model was coupled with a particle-tracking Lagrangian model and used in order to simulate bothsurface water circulation and the transport and diffusion of numerical particles, proxy of jellyfish, inside the area of interest. Besides providing a 4-day forecast for the trajectory of a jellyfish bloom, the developed system can also provide a hindcast for the same trajectory, using archived values for a set of hydrodynamic and biogeochemical parameters still generated through the ROSARIO-SHYFEM system.

In the coming months, the same model will be validated through the analyses of trajectories taken by various typologies of drifters.